We're still not sure how many angels could fit on the head of a pin (that would depend how many nanometers wide an angel is, naturally), but today's advanced micromachining techniques give scientists the ability to fabricate complex objects on a scale never before possible. And things just keep getting more interesting. See for yourself in this gallery of tiny wonders, from miniature submarines capable of sailing through your blood vessels to tiny eyeglasses for houseflies.

